Improving generalized inverted index lock wait times
Andrey Borodin, Sergey Mirvoda, Sergey V. Porshnev, Olga Ponomareva · Journal of Physics Conference Series · 2018
Concurrent operations on tree like data structures is a cornerstone of any database system. Concurrent operations intended for improving read\write performance and usually implemented via some way of locking. Deadlock-free methods of concurrency control are known as tree locking protocols. These protocols provide basic operations(verbs) and algorithm (ways of operation invocations) for applying it to any tree-like data structure. These algorithms operate on data, managed by storage engine which are very different among RDBMS implementations. In this paper, we discuss tree locking protocol implementation for General inverted index (Gin) applied to multiversion concurrency control (MVCC) storage engine inside PostgreSQL RDBMS. After that we introduce improvements to locking protocol and provide usage statistics about evaluation of our improvement in very high load environment in one of the world's largest IT company.